* {
	box-sizing: border-box;
}

html,
body {
	width: 100%;
	height: 100%;
	padding: 0px;
	margin: 0px;
}

/*默认是一个弹性盒子，且水平和垂直都居中*/
.container {
	height: 100%;
	background-repeat: no-repeat;
	display: flex;
	justify-content: center;
	align-items: center;
}